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 * 2. Redistributions in binary form must reproduce the above copyright notice, this list of
 * conditions and the following disclaimer in the documentation and/or other materials provided
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 * 3. Neither the name of the copyright holder nor the names of its contributors may be used to
 * endorse or promote products derived from this software without specific prior written
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 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND ANY EXPRESS
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package com.oracle.truffle.llvm.runtime.interop.export;

import com.oracle.truffle.api.CompilerAsserts;
import com.oracle.truffle.api.TruffleLanguage.ContextReference;
import com.oracle.truffle.api.dsl.Cached;
import com.oracle.truffle.api.dsl.Specialization;
import com.oracle.truffle.llvm.runtime.LLVMContext;
import com.oracle.truffle.llvm.runtime.LLVMLanguage;
import com.oracle.truffle.llvm.runtime.interop.LLVMDataEscapeNode;
import com.oracle.truffle.llvm.runtime.interop.access.LLVMInteropType;
import com.oracle.truffle.llvm.runtime.interop.access.LLVMInteropType.ValueKind;
import com.oracle.truffle.llvm.runtime.interop.convert.ForeignToLLVM;
import com.oracle.truffle.llvm.runtime.interop.export.LLVMForeignAccessNodeFactory.ReadNodeGen;
import com.oracle.truffle.llvm.runtime.interop.export.LLVMForeignAccessNodeFactory.WriteNodeGen;
import com.oracle.truffle.llvm.runtime.nodes.api.LLVMLoadNode;
import com.oracle.truffle.llvm.runtime.nodes.api.LLVMNode;
import com.oracle.truffle.llvm.runtime.nodes.api.LLVMStoreNode;
import com.oracle.truffle.llvm.runtime.pointer.LLVMPointer;

public abstract class LLVMForeignAccessNode {

    public static Read createRead() {
        return ReadNodeGen.create();
    }

    public static Write createWrite() {
        return WriteNodeGen.create();
    }

    public abstract static class Read extends LLVMNode {

        static final int VALUE_KIND_COUNT = ValueKind.values().length;

        public abstract Object execute(LLVMPointer ptr, LLVMInteropType type);

        @Specialization
        Object doStructured(LLVMPointer ptr, @SuppressWarnings("unused") LLVMInteropType.Structured type) {
            // inline structured value, nothing to read
            return ptr;
        }

        @Specialization(guards = "type.getKind() == cachedKind", limit = "VALUE_KIND_COUNT")
        Object doValue(LLVMPointer ptr, LLVMInteropType.Value type,
                        @Cached("type.getKind()") @SuppressWarnings("unused") LLVMInteropType.ValueKind cachedKind,
                        @Cached("createLoadNode(cachedKind)") LLVMLoadNode load,
                        @Cached("create()") LLVMDataEscapeNode dataEscape) {
            Object ret = load.executeWithTarget(ptr);
            return dataEscape.executeWithType(ret, type.getBaseType());
        }

        LLVMLoadNode createLoadNode(LLVMInteropType.ValueKind kind) {
            CompilerAsserts.neverPartOfCompilation();
            ContextReference<LLVMContext> ctxRef = LLVMLanguage.getLLVMContextReference();
            return ctxRef.get().getNodeFactory().createLoadNode(kind);
        }
    }

    public abstract static class Write extends LLVMNode {

        protected abstract void execute(LLVMPointer ptr, LLVMInteropType.Value type, Object value);

        @Specialization(guards = "type.getKind() == cachedKind")
        void doValue(LLVMPointer ptr, LLVMInteropType.Value type, Object value,
                        @Cached("type.getKind()") @SuppressWarnings("unused") LLVMInteropType.ValueKind cachedKind,
                        @Cached("createStoreNode(cachedKind)") LLVMStoreNode store,
                        @Cached("createForeignToLLVM(type)") ForeignToLLVM toLLVM) {
            // since we only cache type.getKind(), not type, we have to use executeWithType
            Object llvmValue = toLLVM.executeWithType(value, type.getBaseType());
            store.executeWithTarget(ptr, llvmValue);
        }

        LLVMStoreNode createStoreNode(LLVMInteropType.ValueKind kind) {
            CompilerAsserts.neverPartOfCompilation();
            ContextReference<LLVMContext> ctxRef = LLVMLanguage.getLLVMContextReference();
            return ctxRef.get().getNodeFactory().createStoreNode(kind);
        }

        protected ForeignToLLVM createForeignToLLVM(LLVMInteropType.Value type) {
            return getNodeFactory().createForeignToLLVM(type);
        }
    }
}
